1. Technical Field
The present invention relates in general to document presentation and in particular to the generation of a presentation-ready document within a data processing system. Still more particularly, the present invention relates to a data processing system and method for efficiently generating a presentation-ready document including both fixed and variable data, wherein a user is not required to manually specify how the fixed and variable data are to be merged.
2. Description of the Related Art
Many industries, for example, the publishing and direct marketing industries, rely heavily on high-speed, high-resolution, large-capacity printing. These industries often make use of so-called Print On Demand (POD) presentation environments that are capable of producing over 400 pages per minute (100 pages per minute in full color) at resolutions of 600 dots per inch or greater. The high performance requirements of a POD presentation environment necessitate the transfer of massive amounts of data to the printhead--on the order of 30 MB per second.
Information to be presented within a POD presentation environment is typically formatted as a document, which comprises both the collection of data objects that constitute the document's content and the resources and formatting specifications that dictate the processing functions to be performed on that content. Documents are constructed of one or more pages, and the pages in turn are made up of data objects such as bar code objects, graphics objects, image objects and presentation text. Each data object has associated layout information that directs the placement and orientation of the data object on the page, as well as the page width, page depth, and other format parameters. In addition to fixed data objects such as presentation text, which may be common to multiple copies of a document, POD architectures also typically support variable data objects, which can be unique to each copy (and each page of each copy) of a document.
Conventional POD presentation environments have typically handled documents including variable data inefficiently. For example, assume that a user desires to produce 100 copies of a one page document for which the fixed data objects in each copy are identical and the variable data objects in each copy are unique. In a conventional POD presentation system, the user first prepares, utilizing a desktop publishing or word processing application, a one page document including both the fixed data and a designation of a variable data area in which variable data objects are to be presented. The user also prepares either a second document or additional pages of the first document that specify the variable data objects. In response to an output command, the application merges the fixed and variable data objects into a lengthy Page Description Language (PDL) file, which specifies the content and format for each of the 100 pages to be printed. The PDL file is then transmitted to a Raster Image Processor (RIP) within the POD presentation system, which executes (hereinafter referred to as "rips") the PDL instructions within the document file in order to obtain 100 pages of dot patterns that are to appear on the physical print medium. Thereafter, the dot patterns are applied to the print medium by the printhead.
Although this prior art method of presenting documents including variable data is relatively simple from the user's perspective, it unnecessarily limits the performance of a POD presentation system by requiring the RIP to repetitively process the fixed data appearing on each of the 100 pages. In order to address this inefficiency, custom applications such as MERGEDOC (available from International Business Machines (IBM) Corporation of Armonk, N.Y.) were developed that permit a user to generate two separate PDL files: a fixed data object file and a variable data object file. In addition, such custom applications provide facilities that enable the user to manually build a "bookticket" that specifies how the fixed and variable data objects are to be merged. In POD presentation systems that employ a custom application, the manually-generated bookticket and the two PDL files are transmitted to the RIP, which processes each of the fixed and variable data objects once and stores the resulting dot patterns. The RIP then merges the variable data objects with the fixed data objects in accordance with the bookticket prepared by the user in order to obtain a presentation-ready document. Although custom applications enhance presentation efficiency by eliminating the need to rip fixed data objects multiple times, the use of custom applications entails a large amount of additional user input in order to specify how the fixed and variable data objects are to be merged.
As should thus be apparent, it would be desirable to provide an improved method and system for presenting documents within a POD presentation environment. In particular, it would be desirable to provide a method and system for automatically generating a presentation-ready document that do not require the user to manually build a bookticket specifying the manner in which the fixed and variable data are to be merged.